xref: /linux-6.15/include/linux/kallsyms.h (revision bcefe12e)
1 /* Rewritten and vastly simplified by Rusty Russell for in-kernel
2  * module loader:
3  *   Copyright 2002 Rusty Russell <[email protected]> IBM Corporation
4  */
5 #ifndef _LINUX_KALLSYMS_H
6 #define _LINUX_KALLSYMS_H
7 
8 #include <linux/errno.h>
9 #include <linux/kernel.h>
10 #include <linux/stddef.h>
11 
12 #define KSYM_NAME_LEN 128
13 #define KSYM_SYMBOL_LEN (sizeof("%s+%#lx/%#lx [%s]") + (KSYM_NAME_LEN - 1) + \
14 			 2*(BITS_PER_LONG*3/10) + (MODULE_NAME_LEN - 1) + 1)
15 
16 struct module;
17 
18 #ifdef CONFIG_KALLSYMS
19 /* Lookup the address for a symbol. Returns 0 if not found. */
20 unsigned long kallsyms_lookup_name(const char *name);
21 
22 /* Call a function on each kallsyms symbol in the core kernel */
23 int kallsyms_on_each_symbol(int (*fn)(void *, const char *, struct module *,
24 				      unsigned long),
25 			    void *data);
26 
27 extern int kallsyms_lookup_size_offset(unsigned long addr,
28 				  unsigned long *symbolsize,
29 				  unsigned long *offset);
30 
31 /* Lookup an address.  modname is set to NULL if it's in the kernel. */
32 const char *kallsyms_lookup(unsigned long addr,
33 			    unsigned long *symbolsize,
34 			    unsigned long *offset,
35 			    char **modname, char *namebuf);
36 
37 /* Look up a kernel symbol and return it in a text buffer. */
38 extern int sprint_symbol(char *buffer, unsigned long address);
39 
40 /* Look up a kernel symbol and print it to the kernel messages. */
41 extern void __print_symbol(const char *fmt, unsigned long address);
42 
43 int lookup_symbol_name(unsigned long addr, char *symname);
44 int lookup_symbol_attrs(unsigned long addr, unsigned long *size, unsigned long *offset, char *modname, char *name);
45 
46 #else /* !CONFIG_KALLSYMS */
47 
48 static inline unsigned long kallsyms_lookup_name(const char *name)
49 {
50 	return 0;
51 }
52 
53 static inline int kallsyms_on_each_symbol(int (*fn)(void *, const char *,
54 						    struct module *,
55 						    unsigned long),
56 					  void *data)
57 {
58 	return 0;
59 }
60 
61 static inline int kallsyms_lookup_size_offset(unsigned long addr,
62 					      unsigned long *symbolsize,
63 					      unsigned long *offset)
64 {
65 	return 0;
66 }
67 
68 static inline const char *kallsyms_lookup(unsigned long addr,
69 					  unsigned long *symbolsize,
70 					  unsigned long *offset,
71 					  char **modname, char *namebuf)
72 {
73 	return NULL;
74 }
75 
76 static inline int sprint_symbol(char *buffer, unsigned long addr)
77 {
78 	*buffer = '\0';
79 	return 0;
80 }
81 
82 static inline int lookup_symbol_name(unsigned long addr, char *symname)
83 {
84 	return -ERANGE;
85 }
86 
87 static inline int lookup_symbol_attrs(unsigned long addr, unsigned long *size, unsigned long *offset, char *modname, char *name)
88 {
89 	return -ERANGE;
90 }
91 
92 /* Stupid that this does nothing, but I didn't create this mess. */
93 #define __print_symbol(fmt, addr)
94 #endif /*CONFIG_KALLSYMS*/
95 
96 /* This macro allows us to keep printk typechecking */
97 static void __check_printsym_format(const char *fmt, ...)
98 __attribute__((format(printf,1,2)));
99 static inline void __check_printsym_format(const char *fmt, ...)
100 {
101 }
102 
103 static inline void print_symbol(const char *fmt, unsigned long addr)
104 {
105 	__check_printsym_format(fmt, "");
106 	__print_symbol(fmt, (unsigned long)
107 		       __builtin_extract_return_addr((void *)addr));
108 }
109 
110 /*
111  * Pretty-print a function pointer.  This function is deprecated.
112  * Please use the "%pF" vsprintf format instead.
113  */
114 static inline void __deprecated print_fn_descriptor_symbol(const char *fmt, void *addr)
115 {
116 #if defined(CONFIG_IA64) || defined(CONFIG_PPC64)
117 	addr = *(void **)addr;
118 #endif
119 	print_symbol(fmt, (unsigned long)addr);
120 }
121 
122 static inline void print_ip_sym(unsigned long ip)
123 {
124 	printk("[<%p>] %pS\n", (void *) ip, (void *) ip);
125 }
126 
127 #endif /*_LINUX_KALLSYMS_H*/
128